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#pragma once
#include "types.hh"
#include "serialise.hh"
namespace nix {
/* dumpPath creates a Nix archive of the specified path. The format
is as follows:
IF path points to a REGULAR FILE:
dump(path) = attrs(
[ ("type", "regular")
, ("contents", contents(path))
])
IF path points to a DIRECTORY:
dump(path) = attrs(
[ ("type", "directory")
, ("entries", concat(map(f, sort(entries(path)))))
])
where f(fn) = attrs(
[ ("name", fn)
, ("file", dump(path + "/" + fn))
])
where:
attrs(as) = concat(map(attr, as)) + encN(0)
attrs((a, b)) = encS(a) + encS(b)
encS(s) = encN(len(s)) + s + (padding until next 64-bit boundary)
encN(n) = 64-bit little-endian encoding of n.
contents(path) = the contents of a regular file.
sort(strings) = lexicographic sort by 8-bit value (strcmp).
entries(path) = the entries of a directory, without `.' and
`..'.
`+' denotes string concatenation. */
void dumpPath(const Path & path, Sink & sink,
PathFilter & filter = defaultPathFilter);
void dumpString(const std::string & s, Sink & sink);
/* FIXME: fix this API, it sucks. */
struct ParseSink
{
virtual void createDirectory(const Path & path) { };
virtual void createRegularFile(const Path & path) { };
virtual void isExecutable() { };
virtual void preallocateContents(uint64_t size) { };
virtual void receiveContents(std::string_view data) { };
virtual void createSymlink(const Path & path, const string & target) { };
};
/* If the NAR archive contains a single file at top-level, then save
the contents of the file to `s'. Otherwise barf. */
struct RetrieveRegularNARSink : ParseSink
{
bool regular = true;
Sink & sink;
RetrieveRegularNARSink(Sink & sink) : sink(sink) { }
void createDirectory(const Path & path) override
{
regular = false;
}
void receiveContents(std::string_view data) override
{
sink(data);
}
void createSymlink(const Path & path, const string & target) override
{
regular = false;
}
};
void parseDump(ParseSink & sink, Source & source);
void restorePath(const Path & path, Source & source);
/* Read a NAR from 'source' and write it to 'sink'. */
void copyNAR(Source & source, Sink & sink);
void copyPath(const Path & from, const Path & to);
extern const std::string narVersionMagic1;
}
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